drivers/staging/dgrp/dgrp_specproc.c

   1 /*
   2  *
   3  * Copyright 1999 Digi International (www.digi.com)
   4  *     James Puzzo  <jamesp at digi dot com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
  13  * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  14  * PURPOSE.  See the GNU General Public License for more details.
  15  *
  16  */
  17
  18 /*
  19  *
  20  *  Filename:
  21  *
  22  *     dgrp_specproc.c
  23  *
  24  *  Description:
  25  *
  26  *     Handle the "config" proc entry for the linux realport device driver
  27  *     and provide slots for the "net" and "mon" devices
  28  *
  29  *  Author:
  30  *
  31  *     James A. Puzzo
  32  *
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/tty.h>
  37 #include <linux/sched.h>
  38 #include <linux/cred.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/ctype.h>
  41 #include <linux/seq_file.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/vmalloc.h>
  44
  45 #include "dgrp_common.h"
  46
  47 static struct proc_dir_entry *dgrp_proc_dir_entry;
  48
  49 static int dgrp_add_id(long id);
  50 static int dgrp_remove_nd(struct nd_struct *nd);
  51 static void unregister_dgrp_device(struct proc_dir_entry *de);
  52 static void register_dgrp_device(struct nd_struct *node,
  53                                  struct proc_dir_entry *root,
  54                                  void (*register_hook)(struct proc_dir_entry *de));
  55
  56 /* File operation declarations */
  57 static int parse_write_config(char *);
  58
  59
  60 static struct inode_operations proc_inode_ops = {
  61         .permission = dgrp_inode_permission
  62 };
  63
  64
  65 static ssize_t dgrp_config_proc_write(struct file *file,
  66                                       const char __user *buffer,
  67                                       size_t count, loff_t *pos);
  68
  69 static int dgrp_nodeinfo_proc_open(struct inode *inode, struct file *file);
  70 static int dgrp_info_proc_open(struct inode *inode, struct file *file);
  71 static int dgrp_config_proc_open(struct inode *inode, struct file *file);
  72
  73 static struct file_operations config_proc_file_ops = {
  74         .owner   = THIS_MODULE,
  75         .open    = dgrp_config_proc_open,
  76         .read    = seq_read,
  77         .llseek  = seq_lseek,
  78         .release = seq_release,
  79         .write   = dgrp_config_proc_write,
  80 };
  81
  82 static struct file_operations info_proc_file_ops = {
  83         .owner   = THIS_MODULE,
  84         .open    = dgrp_info_proc_open,
  85         .read    = seq_read,
  86         .llseek  = seq_lseek,
  87         .release = single_release,
  88 };
  89
  90 static struct file_operations nodeinfo_proc_file_ops = {
  91         .owner   = THIS_MODULE,
  92         .open    = dgrp_nodeinfo_proc_open,
  93         .read    = seq_read,
  94         .llseek  = seq_lseek,
  95         .release = seq_release,
  96 };
  97
  98 static struct proc_dir_entry *net_entry_pointer;
  99 static struct proc_dir_entry *mon_entry_pointer;
 100 static struct proc_dir_entry *dpa_entry_pointer;
 101 static struct proc_dir_entry *ports_entry_pointer;
 102
 103 void dgrp_unregister_proc(void)
 104 {
 105         net_entry_pointer = NULL;
 106         mon_entry_pointer = NULL;
 107         dpa_entry_pointer = NULL;
 108         ports_entry_pointer = NULL;
 109
 110         if (dgrp_proc_dir_entry) {
 111                 struct nd_struct *nd;
 112                 list_for_each_entry(nd, &nd_struct_list, list) {
 113                         if (nd->nd_net_de) {
 114                                 unregister_dgrp_device(nd->nd_net_de);
 115                                 dgrp_remove_node_class_sysfs_files(nd);
 116                         }
 117
 118                         if (nd->nd_mon_de)
 119                                 unregister_dgrp_device(nd->nd_mon_de);
 120
 121                         if (nd->nd_dpa_de)
 122                                 unregister_dgrp_device(nd->nd_dpa_de);
 123
 124                         if (nd->nd_ports_de)
 125                                 unregister_dgrp_device(nd->nd_ports_de);
 126                 }
 127                 remove_proc_entry("dgrp/config", NULL);
 128                 remove_proc_entry("dgrp/info", NULL);
 129                 remove_proc_entry("dgrp/nodeinfo", NULL);
 130                 remove_proc_entry("dgrp/net", NULL);
 131                 remove_proc_entry("dgrp/mon", NULL);
 132                 remove_proc_entry("dgrp/dpa", NULL);
 133                 remove_proc_entry("dgrp/ports", NULL);
 134                 remove_proc_entry("dgrp", NULL);
 135                 dgrp_proc_dir_entry = NULL;
 136         }
 137 }
 138
 139 void dgrp_register_proc(void)
 140 {
 141         struct proc_dir_entry *de;
 142         /*
 143          *      Register /proc/dgrp
 144          */
 145         dgrp_proc_dir_entry = proc_mkdir("dgrp", NULL);
 146         if (!dgrp_proc_dir_entry)
 147                 return;
 148         de = create_proc_entry("dgrp/config", 0644, NULL);
 149         if (de) {
 150                 de->proc_fops = &config_proc_file_ops;
 151                 de->proc_iops = &proc_inode_ops;
 152         }
 153         de = create_proc_entry("dgrp/info", 0644, NULL);
 154         if (de) {
 155                 de->proc_fops = &info_proc_file_ops;
 156                 de->proc_iops = &proc_inode_ops;
 157         }
 158         de = create_proc_entry("dgrp/nodeinfo", 0644, NULL);
 159         if (de) {
 160                 de->proc_fops = &nodeinfo_proc_file_ops;
 161                 de->proc_iops = &proc_inode_ops;
 162         }
 163         net_entry_pointer = proc_mkdir_mode("dgrp/net", 0500, NULL);
 164         mon_entry_pointer = proc_mkdir_mode("dgrp/mon", 0500, NULL);
 165         dpa_entry_pointer = proc_mkdir_mode("dgrp/dpa", 0500, NULL);
 166         ports_entry_pointer = proc_mkdir_mode("dgrp/ports", 0500, NULL);
 167 }
 168
 169 static void *dgrp_config_proc_start(struct seq_file *m, loff_t *pos)
 170 {
 171         return seq_list_start_head(&nd_struct_list, *pos);
 172 }
 173
 174 static void *dgrp_config_proc_next(struct seq_file *p, void *v, loff_t *pos)
 175 {
 176         return seq_list_next(v, &nd_struct_list, pos);
 177 }
 178
 179 static void dgrp_config_proc_stop(struct seq_file *m, void *v)
 180 {
 181 }
 182
 183 static int dgrp_config_proc_show(struct seq_file *m, void *v)
 184 {
 185         struct nd_struct *nd;
 186         char tmp_id[4];
 187
 188         if (v == &nd_struct_list) {
 189                 seq_puts(m, "#-----------------------------------------------------------------------------\n");
 190                 seq_puts(m, "#                        Avail\n");
 191                 seq_puts(m, "# ID  Major  State       Ports\n");
 192                 return 0;
 193         }
 194
 195         nd = list_entry(v, struct nd_struct, list);
 196
 197         ID_TO_CHAR(nd->nd_ID, tmp_id);
 198
 199         seq_printf(m, "  %-2.2s  %-5ld  %-10.10s  %-5d\n",
 200                    tmp_id,
 201                    nd->nd_major,
 202                    ND_STATE_STR(nd->nd_state),
 203                    nd->nd_chan_count);
 204
 205         return 0;
 206 }
 207
 208 static const struct seq_operations proc_config_ops = {
 209         .start = dgrp_config_proc_start,
 210         .next  = dgrp_config_proc_next,
 211         .stop  = dgrp_config_proc_stop,
 212         .show  = dgrp_config_proc_show,
 213 };
 214
 215 static int dgrp_config_proc_open(struct inode *inode, struct file *file)
 216 {
 217         return seq_open(file, &proc_config_ops);
 218 }
 219
 220
 221 /*
 222  *  When writing configuration information, each "record" (i.e. each
 223  *  write) is treated as an independent request.  See the "parse"
 224  *  description for more details.
 225  */
 226 static ssize_t dgrp_config_proc_write(struct file *file,
 227                                       const char __user *buffer,
 228                                       size_t count, loff_t *pos)
 229 {
 230         ssize_t retval;
 231         char *inbuf, *sp;
 232         char *line, *ldelim;
 233
 234         if (count > 32768)
 235                 return -EINVAL;
 236
 237         inbuf = sp = vzalloc(count + 1);
 238         if (!inbuf)
 239                 return -ENOMEM;
 240
 241         if (copy_from_user(inbuf, buffer, count)) {
 242                 retval = -EFAULT;
 243                 goto done;
 244         }
 245
 246         inbuf[count] = 0;
 247
 248         ldelim = "\n";
 249
 250         line = strpbrk(sp, ldelim);
 251         while (line) {
 252                 *line = 0;
 253                 retval = parse_write_config(sp);
 254                 if (retval)
 255                         goto done;
 256
 257                 sp = line + 1;
 258                 line = strpbrk(sp, ldelim);
 259         }
 260
 261         retval = count;
 262 done:
 263         vfree(inbuf);
 264         return retval;
 265 }
 266
 267 /*
 268  *  ------------------------------------------------------------------------
 269  *
 270  *  The following are the functions to parse input
 271  *
 272  *  ------------------------------------------------------------------------
 273  */
 274 static inline char *skip_past_ws(const char *str)
 275 {
 276         while ((*str) && !isspace(*str))
 277                 ++str;
 278
 279         return skip_spaces(str);
 280 }
 281
 282 static int parse_id(char **c, char *cID)
 283 {
 284         int tmp = **c;
 285
 286         if (isalnum(tmp) || (tmp == '_'))
 287                 cID[0] = tmp;
 288         else
 289                 return -EINVAL;
 290
 291         (*c)++; tmp = **c;
 292
 293         if (isalnum(tmp) || (tmp == '_')) {
 294                 cID[1] = tmp;
 295                 (*c)++;
 296         } else
 297                 cID[1] = 0;
 298
 299         return 0;
 300 }
 301
 302 static int parse_add_config(char *buf)
 303 {
 304         char *c = buf;
 305         int  retval;
 306         char cID[2];
 307         long ID;
 308
 309         c = skip_past_ws(c);
 310
 311         retval = parse_id(&c, cID);
 312         if (retval < 0)
 313                 return retval;
 314
 315         ID = CHAR_TO_ID(cID);
 316
 317         c = skip_past_ws(c);
 318
 319         return dgrp_add_id(ID);
 320 }
 321
 322 static int parse_del_config(char *buf)
 323 {
 324         char *c = buf;
 325         int  retval;
 326         struct nd_struct *nd;
 327         char cID[2];
 328         long ID;
 329         long major;
 330
 331         c = skip_past_ws(c);
 332
 333         retval = parse_id(&c, cID);
 334         if (retval < 0)
 335                 return retval;
 336
 337         ID = CHAR_TO_ID(cID);
 338
 339         c = skip_past_ws(c);
 340
 341         retval = kstrtol(c, 10, &major);
 342         if (retval)
 343                 return retval;
 344
 345         nd = nd_struct_get(major);
 346         if (!nd)
 347                 return -EINVAL;
 348
 349         if ((nd->nd_major != major) || (nd->nd_ID != ID))
 350                 return -EINVAL;
 351
 352         return dgrp_remove_nd(nd);
 353 }
 354
 355 static int parse_chg_config(char *buf)
 356 {
 357         return -EINVAL;
 358 }
 359
 360 /*
 361  *  The passed character buffer represents a single configuration request.
 362  *  If the first character is a "+", it is parsed as a request to add a
 363  *     PortServer
 364  *  If the first character is a "-", it is parsed as a request to delete a
 365  *     PortServer
 366  *  If the first character is a "*", it is parsed as a request to change a
 367  *     PortServer
 368  *  Any other character (including whitespace) causes the record to be
 369  *     ignored.
 370  */
 371 static int parse_write_config(char *buf)
 372 {
 373         int retval;
 374
 375         switch (buf[0]) {
 376         case '+':
 377                 retval = parse_add_config(buf);
 378                 break;
 379         case '-':
 380                 retval = parse_del_config(buf);
 381                 break;
 382         case '*':
 383                 retval = parse_chg_config(buf);
 384                 break;
 385         default:
 386                 retval = -EINVAL;
 387         }
 388
 389         return retval;
 390 }
 391
 392 static int dgrp_info_proc_show(struct seq_file *m, void *v)
 393 {
 394         seq_printf(m, "version: %s\n", DIGI_VERSION);
 395         seq_puts(m, "register_with_sysfs: 1\n");
 396         seq_printf(m, "pollrate: 0x%08x\t(%d)\n",
 397                    dgrp_poll_tick, dgrp_poll_tick);
 398
 399         return 0;
 400 }
 401
 402 static int dgrp_info_proc_open(struct inode *inode, struct file *file)
 403 {
 404         return single_open(file, dgrp_info_proc_show, NULL);
 405 }
 406
 407
 408 static void *dgrp_nodeinfo_start(struct seq_file *m, loff_t *pos)
 409 {
 410         return seq_list_start_head(&nd_struct_list, *pos);
 411 }
 412
 413 static void *dgrp_nodeinfo_next(struct seq_file *p, void *v, loff_t *pos)
 414 {
 415         return seq_list_next(v, &nd_struct_list, pos);
 416 }
 417
 418 static void dgrp_nodeinfo_stop(struct seq_file *m, void *v)
 419 {
 420 }
 421
 422 static int dgrp_nodeinfo_show(struct seq_file *m, void *v)
 423 {
 424         struct nd_struct *nd;
 425         char hwver[8];
 426         char swver[8];
 427         char tmp_id[4];
 428
 429         if (v == &nd_struct_list) {
 430                 seq_puts(m, "#-----------------------------------------------------------------------------\n");
 431                 seq_puts(m, "#                 HW       HW   SW\n");
 432                 seq_puts(m, "# ID  State       Version  ID   Version  Description\n");
 433                 return 0;
 434         }
 435
 436         nd = list_entry(v, struct nd_struct, list);
 437
 438         ID_TO_CHAR(nd->nd_ID, tmp_id);
 439
 440         if (nd->nd_state == NS_READY) {
 441                 sprintf(hwver, "%d.%d", (nd->nd_hw_ver >> 8) & 0xff,
 442                         nd->nd_hw_ver & 0xff);
 443                 sprintf(swver, "%d.%d", (nd->nd_sw_ver >> 8) & 0xff,
 444                         nd->nd_sw_ver & 0xff);
 445                 seq_printf(m, "  %-2.2s  %-10.10s  %-7.7s  %-3d  %-7.7s  %-35.35s\n",
 446                            tmp_id,
 447                            ND_STATE_STR(nd->nd_state),
 448                            hwver,
 449                            nd->nd_hw_id,
 450                            swver,
 451                            nd->nd_ps_desc);
 452
 453         } else {
 454                 seq_printf(m, "  %-2.2s  %-10.10s\n",
 455                            tmp_id,
 456                            ND_STATE_STR(nd->nd_state));
 457         }
 458
 459         return 0;
 460 }
 461
 462
 463 static const struct seq_operations nodeinfo_ops = {
 464         .start = dgrp_nodeinfo_start,
 465         .next  = dgrp_nodeinfo_next,
 466         .stop  = dgrp_nodeinfo_stop,
 467         .show  = dgrp_nodeinfo_show,
 468 };
 469
 470 static int dgrp_nodeinfo_proc_open(struct inode *inode, struct file *file)
 471 {
 472         return seq_open(file, &nodeinfo_ops);
 473 }
 474
 475 /**
 476  * dgrp_add_id() -- creates new nd struct and adds it to list
 477  * @id: id of device to add
 478  */
 479 static int dgrp_add_id(long id)
 480 {
 481         struct nd_struct *nd;
 482         int ret;
 483         int i;
 484
 485         nd = kzalloc(sizeof(struct nd_struct), GFP_KERNEL);
 486         if (!nd)
 487                 return -ENOMEM;
 488
 489         nd->nd_major = 0;
 490         nd->nd_ID = id;
 491
 492         spin_lock_init(&nd->nd_lock);
 493
 494         init_waitqueue_head(&nd->nd_tx_waitq);
 495         init_waitqueue_head(&nd->nd_mon_wqueue);
 496         init_waitqueue_head(&nd->nd_dpa_wqueue);
 497         for (i = 0; i < SEQ_MAX; i++)
 498                 init_waitqueue_head(&nd->nd_seq_wque[i]);
 499
 500         /* setup the structures to get the major number */
 501         ret = dgrp_tty_init(nd);
 502         if (ret)
 503                 goto error_out;
 504
 505         nd->nd_major = nd->nd_serial_ttdriver->major;
 506
 507         ret = nd_struct_add(nd);
 508         if (ret)
 509                 goto error_out;
 510
 511         register_dgrp_device(nd, net_entry_pointer, dgrp_register_net_hook);
 512         register_dgrp_device(nd, mon_entry_pointer, dgrp_register_mon_hook);
 513         register_dgrp_device(nd, dpa_entry_pointer, dgrp_register_dpa_hook);
 514         register_dgrp_device(nd, ports_entry_pointer,
 515                               dgrp_register_ports_hook);
 516
 517         return 0;
 518
 519         /* FIXME this guy should free the tty driver stored in nd and destroy
 520          * all channel ports */
 521 error_out:
 522         kfree(nd);
 523         return ret;
 524
 525 }
 526
 527 static int dgrp_remove_nd(struct nd_struct *nd)
 528 {
 529         int ret;
 530
 531         /* Check to see if the selected structure is in use */
 532         if (nd->nd_tty_ref_cnt)
 533                 return -EBUSY;
 534
 535         if (nd->nd_net_de) {
 536                 unregister_dgrp_device(nd->nd_net_de);
 537                 dgrp_remove_node_class_sysfs_files(nd);
 538         }
 539
 540         unregister_dgrp_device(nd->nd_mon_de);
 541
 542         unregister_dgrp_device(nd->nd_ports_de);
 543
 544         unregister_dgrp_device(nd->nd_dpa_de);
 545
 546         dgrp_tty_uninit(nd);
 547
 548         ret = nd_struct_del(nd);
 549         if (ret)
 550                 return ret;
 551
 552         kfree(nd);
 553         return 0;
 554 }
 555
 556 static void register_dgrp_device(struct nd_struct *node,
 557                                  struct proc_dir_entry *root,
 558                                  void (*register_hook)(struct proc_dir_entry *de))
 559 {
 560         char buf[3];
 561         struct proc_dir_entry *de;
 562
 563         ID_TO_CHAR(node->nd_ID, buf);
 564
 565         de = create_proc_entry(buf, 0600 | S_IFREG, root);
 566         if (!de)
 567                 return;
 568
 569         de->data = (void *) node;
 570
 571         if (register_hook)
 572                 register_hook(de);
 573
 574 }
 575
 576 static void unregister_dgrp_device(struct proc_dir_entry *de)
 577 {
 578         if (!de)
 579                 return;
 580
 581         /* Don't unregister proc entries that are still being used.. */
 582         if ((atomic_read(&de->count)) != 1) {
 583                 pr_alert("%s - proc entry %s in use. Not removing.\n",
 584                          __func__, de->name);
 585                 return;
 586         }
 587
 588         remove_proc_entry(de->name, de->parent);
 589         de = NULL;
 590 }